Use of an extract of at least one vaccinium-type plant as an anti-glycation agent

ABSTRACT

The invention relates to the use of at least one extract of at least one Vaccinium-type plant as the active agent in a composition or for producing a composition, in a physiologically suitable medium, said extract or said composition being intended to reduce or even inhibit the glycation of proteins, especially proteins of the skin or associated structures.

[0001] The present invention relates to the use, as active ingredient,in a physiologically acceptable medium, of at least one extract of atleast one plant of the genus Vaccinium in a composition or for thepreparation of a composition, the extract or the composition beingintended for reducing or even inhibiting glycation of proteins,particularly proteins of the skin and/or of its annexes.

[0002] Glycation is a nonenzymatic process involving a monosaccharide(glucose or ribose) which reacts according to the Maillard reaction withan amino group of an amino acid residue (such as for example lysine),particularly an amino acid residue of a protein, to form a Schiff base.The latter, after a molecular rearrangement called Amadorirearrangement, may lead, through a succession of reactions, to bridging,particularly intramolecular bridging such as for example of thepentosidine type.

[0003] This phenomenon increases regularly with age. It is characterizedby the appearance of glycation products whose content increasesregularly with age. The glycation products are for example pyrraline,carboxymethyllysine, pentosidine, crossline, N^(ε)(2-25carboxyethyl)lysine (CEL), glyoxallysine dimer (GOLD),methylglyoxallysine dimer (MOLD), 3DG-ARG imidazolone, versperlysines A,B, C, threosidine or alternatively advanced glycosylation end-productsor AGEs.

[0004] The glycation of proteins is therefore a universal phenomenon,well known for the skin, particularly for its dermal component, butwhich also occurs in the annexes thereof such as the nails or the hair,particularly on the keratins and marginally in any protein system if theconditions required for glycation exist.

[0005] The human skin consists of two compartments, namely a superficialcompartment, the epidermis, and a deep compartment, the dermis.

[0006] The natural human epidermis is mainly composed of three types ofcells which are the keratinocytes, which are in the great majority, themelanocytes and the Langerhans' cells. Each of these cell typescontributes, through its specific functions, to the essential roleplayed in the body by the skin.

[0007] The dermis provides the epidermis a solid support. It is also itsfeeder component. It consists mainly of fibroblasts and of anextracellular matrix which is itself composed of various extracellularproteins, among which are in particular collagen fibres, elastin andvarious glycoproteins. All these extracellular components aresynthesized by the fibroblast. Also present in the dermis areleukocytes, mastocytes and tissue macrophages. Finally, the dermiscontains blood vessels and nerve fibres.

[0008] The fibroblast, by virtue of its activity in the synthesis of theextracellular matrix proteins (proteoglycans, collagen fibres and otherstructural glycoproteins) is the principal player in the structuralformation of the dermis.

[0009] Collagen fibres are responsible for the strength of the dermis.They are very resistant but sensitive to certain enzymes generallycalled collagenases. In the dermis, the collagen fibres consist offibrils which are firmly attached to each other, thus forming more thanten types of different structures. The structure of the dermis is ingreat part due to the entanglement of the packed collagen fibres. Thecollagen fibres participate in the tonicity of the skin.

[0010] Collagen fibres are regularly renewed but this renewal decreaseswith age, which causes in particular thinning of the dermis. It is alsoaccepted that extrinsic factors such as ultraviolet rays, tobacco andsome treatments (retinoic acid and derivatives, glucocorticoids, vitaminD and derivatives for example) also have an effect on the skin and onits collagen level.

[0011] In the dermal component of the skin, glycation occurs mainly inthe dermis, on the collagen fibres, according to the process describedabove. The glycation of collagen increases regularly with age, causing aregular increase in the content of glycation products in the skin.

[0012] Without wishing to introduce any theory of skin ageing, it shouldbe noted that other modifications of collagen which may also be aconsequence of glycation, such as a reduction in heat denaturation, anincrease in the resistance to enzymatic digestion and an increase inintermolecular bridgings, have been able to be demonstrated during skinageing (Tanaka S. et al., 1988, J. Mol. Biol., 203, 495-505; TakahashiM. et al., 1995, Analytical Biochemistry, 232, 158-162). Furthermore,modifications due to glycation of certain constituents of the basalmembrane, such as collagen IV, laminin and fibronectin have been able tobe demonstrated (Tarsio J F. et al.,1985, Diabetes, 34, 477-484; TarsioJ F. et al., 1988, Diabetes, 37 532-539; Sternberg M. et al., 1995, C.R.Soc. Biol., 189, 967-985).

[0013] Thus, it can be understood why during skin ageing thephysicochemical properties of collagen are modified and it becomes moredifficult to solubilize and more difficult to degrade.

[0014] Thus, one of the components of aged skin indeed appears to beglycated collagen.

[0015] It is very well known that the skin results from a closeassociation between at least two compartments constituting it, namelythe epidermis and the dermis. The interactions between the dermis andthe epidermis are such that it is reasonable to think that amodification of one can have consequences on the other. It can besuspected that the ageing of the dermis in particular, with itsglycation phenomena, is bound to have consequences on the epidermiswhich is associated with it. Thus, during skin ageing, the glycation ofcollagen should result in modifications of the epidermis whichnecessarily participate in the ageing of the epidermis.

[0016] Thus, if the glycation of the proteins of the dermis,particularly of collagen causes as many damaging consequences on theskin, similar consequences are to be expected of the glycation ofproteins on the annexes of the skin, such as for example the nailsand/or the hair and in fact on any protein system.

[0017] It is therefore possible to understand the importance of havingproducts which reduce or even inhibit the phenomenon of glycation ofproteins.

[0018] In this regard, the applicant has surprisingly and unexpectedlydiscovered that extracts of plants of the genus Vaccinium have theproperty of reducing or even inhibiting the phenomenon of glycation ofproteins.

[0019] Plants of the genus Vaccinium belong to the Ericaceae familywhich comprises about one hundred genera.

[0020] In the prior art, extracts of plants of the Ericaceae family areused, inter alia, as antioxidants.

[0021] However, the capacity of extracts of plants of the genusVaccinium to reduce or even inhibit the phenomena of glycation has neverbeen described up until now.

[0022] The subject of the invention is therefore the use, in acomposition or for the preparation of a composition, of an effectivequantity of at least one extract of at least one plant of the genusVaccinium, the extract or the composition being intended for reducing oreven inhibiting the glycation of proteins, particularly the glycation ofthe proteins of the skin and/or of its annexes.

[0023] The expression active ingredient is understood to mean anymolecule or extract capable of modifying or of modulating thefunctioning of at least one given biological system.

[0024] Most particularly, the subject of the invention is the use, in acomposition or for the preparation of a composition, of an effectivequantity of at least one extract of at least one plant of the genusVaccinium, the extract or the composition being intended for reducing oreven inhibiting the glycation of the proteins of the dermis, such as forexample collagen, and/or of the nails and/or of the hair, such as forexample keratins.

[0025] Thus, the subject of the invention is the use, in a compositionor for the preparation of a composition, of an effective quantity of atleast one extract of at least one plant of the genus Vaccinium, theextract or the composition being intended for treating, preventivelyand/or curatively, the signs of ageing of the skin or of its annexeslinked to glycation.

[0026] The genus Vaccinium comprises more than 450 species, among whichthere may be mentioned the species Vaccinium myrtillus, Vacciniumangustifollium, Vaccinium arboreum, Vaccinium arctostaphylos, Vacciniumcaespitosum, Vaccinium corymbosum, Vaccinium hirsutum, Vacciniummacrocarpum, Vaccinium ovatum, Vaccinium oxycoccos, Vaccinium stamineum,Vaccinium uliginosum, Vaccinium urceolatum and Vaccinium vitis-idaea.

[0027] Thus, the extract of a plant of the genus Vaccinium of theinvention is an extract prepared from material derived from at least oneplant belonging to a species chosen from the species Vacciniummyrtillus, Vaccinium angustifollium, Vaccinium arboreum, Vacciniumarctostaphylos, Vaccinium caespitosum, Vaccinium corymbosum, Vacciniumhirsutum, Vaccinium macrocarpum, Vaccinium ovatum, Vaccinium oxycoccos,Vaccinium stamineum, Vaccinium uliginosum, Vaccinium urceolatum andVaccinium vitis-idaea.

[0028] Preferably, according to the invention, the plant belongs to thespecies Vaccinium angustifollium.

[0029] The extract of at least one plant of the genus Vaccinium may beany extract prepared from any plant material derived from at least oneplant of the genus Vaccinium.

[0030] Thus, the extract of at least one plant of the genus Vacciniumused according to the invention may be obtained from plant materialderived from a whole plant or from a plant portion such as the leaves,the stems, the flowers, the petals, the fruit, the roots ordedifferentiated cells.

[0031] The expression dedifferentiated plant cells is understood to meanany plant cell not having any of the characteristics of a particularspecialization and which is capable of living by itself and not independence on other cells. These undifferentiated plant cells arepotentially capable, under the effect of induction, of anydifferentiation in accordance with their genome.

[0032] Depending on the method of culture chosen, and in particulardepending on the culture medium chosen, it is possible to obtain, fromthe same explant, dedifferentiated plant cells having differentcharacteristics.

[0033] Preferably, the fruits are used according to the invention.

[0034] The extract of at least one plant of the genus Vaccinium may beany extract prepared from any plant material derived from at least oneplant of the genus Vaccinium cultured in vivo or derived from in vitroculture.

[0035] The expression in vivo culture is understood to mean anyconventional type culture, that is to say in soil in the open air or ina greenhouse, or soil-free culture. The expression in vitro isunderstood to mean all the techniques known to a person skilled in theart which make it possible artificially to obtain a plant or a portionof a plant. The selection pressure imposed by the physicochemicalconditions during the growth of the plant cells in vitro makes itpossible to obtain a standardized plant material which is availablethroughout the year, unlike the plants cultured in vivo.

[0036] Preferably, a plant derived from in vivo culture is usedaccording to the invention.

[0037] Any method of extraction known to a person skilled in the art maybe used to prepare the extract contained in the composition according tothe invention.

[0038] There may be mentioned in particular aqueous extracts, alcoholicextracts or extracts using an organic solvent.

[0039] The expression aqueous solvent is understood to mean any solventwhich completely or partly consists of water. There may thus bementioned water itself, aqueous-alcoholic solvents in any proportion oralternatively solvents consisting of water and a compound such aspropylene glycol in any proportion.

[0040] Ethanol may be cited in particular among the alcoholic solvents.

[0041] It is also possible to use an extract prepared by the methoddescribed in French patent application No. 95-02379 filed by theapplicant.

[0042] Thus, in a first step, the plant material is ground in an aqueoussolution at low temperature, in a second step, the particles insuspension are removed from the aqueous solution derived from the firststep, and in a third step, the aqueous solution derived from the secondstep is sterilized. This aqueous solution corresponds to the extract.

[0043] Moreover, the first step may be advantageously replaced by asimple operation of freezing the plant tissues (for example at −20°C.),followed by an aqueous extraction repeating the second and thirdsteps described above.

[0044] Regardless of the mode of preparation used according to theinvention, subsequent steps intended to promote preservation and/orstabilization may be added, without as a result, modifying the actualnature of the extract. Thus, for example, the extract obtained may befreeze-dried by any conventional freeze-drying method. A powder is thusobtained which may be used directly or alternatively mixed in anappropriate solvent before use.

[0045] Preferably, according to the invention, there is used an aqueousextract and still more preferably an extract made with a solventcomposed of water and propylene glycol, such as for example Herbasol®sold by the company COSMETOCHEM's.

[0046] According to the invention, the extracts of at least one plant ofthe genus Vaccinium may be used alone or in the form of mixtures of anytype and may be of natural or synthetic origin.

[0047] In particular, the extract of at least one plant of the genusVaccinium or the composition containing it is used according to theinvention for topical application to the skin and/or the nails and/orthe hair.

[0048] The quantity of extract of at least one plant of the genusVaccinium which can be used according to the invention quite obviouslydepends on the desired effect and should be in a quantity which iseffective to reduce or even inhibit glycation.

[0049] By way of example, the quantity of extract of at least one plantof the genus Vaccinium which can be used according to the invention mayrange, for example, from 0.001% to 25% and preferably from 0.005% to 15%of the total weight of the composition.

[0050] In addition, the composition of the invention is used for aperiod sufficient to obtain the effects which are expected according tothe invention. To give an order of magnitude, this duration may be aminimum of 3 weeks, but may also be more than 4 weeks, or even more than8 weeks.

[0051] The composition is preferably intended for cosmetic ordermatological use, advantageously for cosmetic use.

[0052] The composition of the invention intended for topical applicationcontains a physiologically acceptable medium, that is to say which iscompatible with the skin including the scalp, its annexes, the mucousmembranes and/or the eyes and may constitute in particular a cosmetic ordermatological composition.

[0053] This composition may be provided in all the galenic formsnormally used in the cosmetic and dermatological fields, and it may inparticular be in the form of an optionally gelled aqueous solution, anoptionally two-phase dispersion of the lotion type, an emulsion obtainedby dispersing a fatty phase in an aqueous phase (O/W) or conversely(W/O), or a triple emulsion (W/O/W or O/W/O) or a vesicular dispersionof the ionic and/or nonionic type. These compositions are preparedaccording to customary methods.

[0054] The composition of the invention may constitute, for example, alotion, a gel, a cream or a milk, and for example a make-up-removing orcleansing lotion or milk, a shampoo or a shower gel.

[0055] The subject of the invention is also a method of cosmetictreatment for treating the signs of ageing linked to the glycation ofproteins, particularly of the skin and/or the nails and/or the hair,characterized in that there is applied to the skin and/or the nailsand/or the hair a cosmetic composition comprising an effective quantityof at least one extract of at least one plant of the genus Vaccinium,the extract or the composition being intended for inhibiting glycation.

[0056] Other characteristics and advantages of the invention will emergemore clearly from the following examples given by way of illustrationand without limitation. In the text which follows or in the precedingtext, the proportions are given in percent by weight, unless otherwisestated.

EXAMPLE 1

[0057] Study of the effect of an extract of Vaccinium angustifollium(bilberry) on glycation.

[0058] A solution of bovine serum albumin at 5 mg/ml in solution inphosphate buffered saline (PBS) is 15 incubated at 37° C. for 28 days inthe presence or in the absence of D-ribose at a concentration 10 mM orof an extract of bilberry at the concentrations of 5% and 10%.

[0059] The glycation is evaluated by measuring the fluorescence (Rx) ofthe AGEs (range of glycation products) at λem.=440 nm emitted by eachsample after excitation at λex.=370 nm or alternatively at λem.=380 nmemitted by each sample after excitation at λex.=320 nm (fluorescenceemitted by some of the glycation products including in particularpentosidine).

[0060] The inhibition of glycation is visualized by the reduction influoresence compared with the sample treated with the sugar alone (R)according to the formula:

(R−Rx)/R×100

[0061] The results are in % inhibition: Extract at Extract at 5% 10%λem. = 440 nm/λex. = 370 nm 63 71 λem. = 380 nm/λex. − 320 nm 16 43

[0062] The bilberry extract has an advantageous antiglycation effectfrom the concentration of 5%.

EXAMPLE 2

[0063] Examples of formulations illustrating the invention andparticularly the compositions according to the invention. Thesecompositions were obtained by simply mixing the different components.Composition 1: Lotion Herbasol ® (extract of Vaccinium 1.00angustifollium) Antioxidant 0.05 Isopropanol 40.00 Preservative 0.30Water qs 100% Composition 2: Treatment gel Herbasol ® (extract ofVaccinium 4.00 angustifollium) Hydroxypropylcellulose* 1.00 Antioxidant0.05 Isopropanol 40.00 Preservative 0.30 Water qs 100% Composition 3:Treatment cream (oil- in-water emulsion) Herbasol ® (extract ofVaccinium 5.00 angustifollium) Glyceryl stearate 2.00 Polysorbate 60**1.00 Stearic acid 1.40 Triethanolamine 0.70 Carbomer 0.40 Liquidfraction of shea butter 12.00 Perhydrosqualene 12.00 Antioxidant 0.05Perfume 0.5 Preservative 0.30 Water qs 100% Composition 4: ShampooHerbasol ® (extract of Vaccinium 2.00 angustifollium)Hydroxypropylcellulose* 1.00 Sodium lauryl sulphate 12.00 Perfume 0.50Preservative 0.30 Water qs 100% Composition 5: Care cream (oil/wateremulsion) Herbasol ® (extract of Vaccinium 4.00 angustifollium) Glycerylstearate 2.00 Polysorbate 60** 1.00 Stearic acid 1.405-n-octanoylsalicylic acid 0.50 Triethanolamine 0.70 Carbomer 0.40Liquid fraction of shea butter 12.00 Perhydrosqualene 12.00 Antioxidant0.05 Perfume 0.5 Preservative 0.30 Water qs 100% Composition 6: GelHerbasol ® (extract of Vaccinium 10.00 angustifollium)Hydroxypropylcellulose* 1.00 Antioxidant 0.05 Lidocaine hydrochloride2.00 Isopropanol 40.00 Preservative 0.30 Water qs 100% Composition 7:Treatment cream (oil-in- water emulsion) Herbasol ® (extract ofVaccinium 20.00 angustifollium) Glyceryl stearate 2.00 Polysorbate 60**1.00 Stearic acid 1.40 Glycyrrhetinic acid 2.00 Triethanolamine 0.70Carbomer 0.40 Liquid fraction of shea butter 12.00 Sunflower oil 10.00Antioxidant 0.05 Perfume 0.5 Preservative 0.30 Water qs 100% Composition8: Gel Herbasol ® (extract of Vaccinium 8.00 angustifollium)All-trans-retinoic acid 0.05 Hydroxypropylcellulose* 1.00 Antioxidant0.05 Isopropanol 40.00 Preservative 0.30 Water qs 100%

1. Use, in a composition or for the preparation of a composition, of aneffective quantity of at least one extract of at least one plant of thegenus Vaccinium, the extract or the composition being 10 intended forreducing glycation.
 2. Use according to the preceding claim,characterized in that the glycation is the glycation of proteins.
 3. Useaccording to any one of the 15 preceding claims, characterized in thatthe proteins are proteins of the skin and/or the nails and/or the hair.4. Use according to the preceding claim, characterized in that theproteins of the skin are 20 proteins of the dermis.
 5. Use according tothe preceding claim, for reducing the glycation of collagen.
 6. Useaccording to claim 3, characterized in that the proteins of the nailsand/or the hair are 25 keratins.
 7. Use according to any one of thepreceding claims, for treating, preventively and/or curatively, thesigns of ageing of the skin and/or of its annexes linked to glycation.8. Use according to any one of the 5 preceding claims, characterized inthat the plant of the genus Vaccinium is of a species chosen from thespecies Vaccinium myrtillus, Vaccinium angustifollium, Vacciniumarboreum, Vaccinium arctostaphylos, Vaccinium caespitosum, Vacciniumcorymbosum, Vaccinium hirsutum, Vaccinium macrocarpum, Vaccinium ovatum,Vaccinium oxycoccos, Vaccinium stamineum, Vaccinium uliginosum,Vaccinium urceolatum and Vaccinium vitis-idaea.
 9. Use according to thepreceding claim, characterized in that the plant of the genus Vacciniumis of the species Vaccinium angustifollium.
 10. Use according to any oneof the preceding claims, characterized in that the extract of at leastone plant of the genus Vaccinium is present in a quantity ranging from0.001% to 25% of the total weight of the composition.
 11. Use accordingto the preceding claim, characterized in that the extract of at leastone plant of the genus Vaccinium is present in a quantity ranging from0.005% to 15% of the total weight of the 25 composition.
 12. Method ofcosmetic treatment for treating the signs of ageing linked to theglycation of proteins of the skin and/or the nails and/or the hair,characterized in that there is applied to the skin and/or the nailsand/or the hair a cosmetic composition comprising an effective quantityof at least one extract of at least one plant of the genus Vaccinium,the extract or the composition being intended for inhibiting glycation.